This invention relates to an apparatus for oxygenating a liquid, i.e., preparing the liquid in solution with oxygen, a method for oxygenating the liquid, and applications of liquids oxygenated by the inventive apparatus and method. The liquid to be oxygenated may be water, for example, or any of a number of other liquids.
It is known that various types of liquids are oxygenated to achieve various results. For example, consumption of an oxygen enriched beverage has a favorable effect on well-being and physical performance, for it provides oxygen to the bloodstream through the stomach lining or intestinal wall. In one case, eight test subjects of various ages and differing sex had their blood oxygen contents and their pulse rates determined. Each subject then drank between xc2xd and xc2xe liters of highly oxygenated water. A short period after ingestion of the enriched water, evidence of a pulmonary function bypass was observed through an average blood oxygen level increase of about 30%, and the effect of a concomitant cardiac relief was observed through an average pulse rate reduction of about 10%. Further, the added oxygen tends to reduce the tartness of any carbonation and does not impart any taste to the resulting liquid.
As a further example, aerobic processes advantageously employ oxygen-containing liquids. As used throughout the specification and the claims, reference to an xe2x80x9caerobicxe2x80x9d process generally includes all chemical and microbiological processes in which a chemical or microbiological process is carried out or is promoted in a liquid medium in the presence of oxygen. Suitable aerobic processes in which an oxygenated liquid can be advantageously employed include, for example, processes in which heretofore water has been aerated such as by bubbling air thereinto, and also in situ or ex situ bioremediation of contaminated (e.g., with petroleum products) or oxygen-depleted bodies of water; wastewater, sludge and animal waste treatment, both by fixed film and by suspended growth methods; rehabilitation of atrophying lakes; biological oxygen demand (BOD) reduction techniques; fresh water aquaculture (e.g., fish farming); salt water aquaculture (e.g., shrimp farming); hydroponic agriculture; odor suppression barriers for anaerobic processes; and insolubilization of dissolved contaminates (e.g., iron, and manganese ions) for removal by filtration or sedimentation.
It is also known that some fermentation processes, i.e., processes which involve fermenting a fermentation liquor, commonly employed in drug production or food processing by microorganisms, benefit from the fermentation liquor being comprised of an oxygenated liquid.
It is also known that numerous types of therapeutic processes can benefit from the use of oxygenated liquids. xe2x80x9cTherapeuticxe2x80x9d processes, as used throughout the specification and the claims, involve the oxygenation of the body or its parts by treatment with an agent in a liquid vehicle containing dissolved oxygen. Suitable therapeutic processes in which an oxygenated liquid can be advantageously employed include, for example, processes for increasing the oxygen content of blood and tissues; oxygenation of wounds to increase the rate of healing and to reduce infections; oxygenated organ transplant storage media; tumor oxygenation for radiation therapy and chemotherapy; lung bypass by oxygenated liquids in case of pulmonary deficiencies; treatment for carbon monoxide poisoning; mouthwashes, dentifrices; topical, including cosmetic treatment media; contact lens treating solutions; and cell level therapeutic applications.
Moreover, it is known that oxygenated liquids can be advantageously employed as solvents for physiological saline isotonic solutions, especially when kept in sealed, sterile containers. Such saline solutions may be prepared by dissolving a sodium concentrate into an oxygen enriched liquid. Alternatively, prepared saline solutions may themselves be subjected to the oxygenation process. Oxygenated saline solutions can provide a more direct and efficient way of providing oxygen to the bloodstream than having the oxygen absorbed thereinto through the stomach lining or intestinal wall, as is done through consumption of an oxygenated beverage.
As a further example, oxygenated liquids may be advantageously employed in some disinfection processes. Such disinfection processes are those in which a very high level of dissolved oxygen serves to kill microbial life in the same manner as does chlorine or ozone. These oxygen concentration levels would exceed those resulting after dilution in a biomass for aerobic treatment thereof as described above. For example, it was found that bacteria in a petri dish was killed when merely subjected to oxygen-enriched water having a dissolved oxygen level of about 50 to 70 mg/l. It has also previously been speculated that rather than subjecting certain microbial life to a disinfectant comprising an oxygenated liquid, a disinfection process may instead involve oxygenating a liquid contaminated with microbial life, whereby the disinfection would take place during the oxygenation process.
Regardless of the use to which oxygenated liquids are put, means for achieving increased levels of dissolved oxygen in a liquid efficiently is desirable, as are means for doing so at high rates of production.
Currently, among the most effective methods and apparatuses for saturating a liquid with oxygen on an industrial scale are those disclosed in U.S. Pat. No. 5,766,490, issued Jun. 16, 1998, and entitled xe2x80x9cOxygenating Apparatus, Method For Oxygenating Water fan Therewith, and Applications Thereofxe2x80x9d, which is expressly incorporated herein by reference, and in U.S. Pat. No. 6,120,008, issued Sep. 19, 2000, and entitled xe2x80x9cOxygenating Apparatus, Method For Oxygenating a Liquid Therewith, and Applications Thereofxe2x80x9d, which is also expressly incorporated herein by reference.
According to the process disclosed by U.S. Pat. No. 5,766,490, a sealed enriching space is provided which includes a venturi mixer through which liquid to be oxygenated upwardly flows, the oxygen gas introduced to the liquid in the venturi throat. This method and apparatus works well, producing an oxygen-enriched liquid having at least 40 mg/l of dissolved oxygen at a rate of approximately 50,000 gallons per day (gpd), but does not take full advantage of the mixing potential offered by a venturi mixer or injector.
According to the process disclosed by U.S. Pat. No. 6,120,008, a sealed enriching space is provided which includes a single venturi mixer through which liquid to be oxygenated flows downwardly, the oxygen gas introduced to the liquid in the venturi throat. The pressure of the liquid/oxygen admixture is raised as it flows through a diffuser as it exits the venturi, whereby the buoyancy of the oxygen bubbles therein is increased. These large bubbles float upwards against the downward admixture flow and are broken up into smaller bubbles by a shock wave established in the diffuser by the high rate of liquid flow therethrough. The smaller bubbles are more readily absorbed into the admixture. This method and apparatus works well, producing an oxygen enriched liquid having 160 mg/l oxygen at a rate of approximately 100,000 gpd.
A method and apparatus for producing an oxygen enriched liquid having even greater oxygen concentrations than may be achieved through prior apparatuses and processes is desirable, particularly where the higher oxygen concentrations is realized in a liquid post-process at atmospheric pressure.
Further, an apparatus which may be easily cleaned in place by providing a reverse flow of a cleaning liquid therethrough, which is particularly useful in liquid food preparation environments, is also desirable.
Throughout the specification, drawings and the claims, xe2x80x9cwaterxe2x80x9d is meant to include any still or effervescent liquid intended to be enriched with oxygen, and xe2x80x9cliquidxe2x80x9d is meant to include water and any other still or effervescent liquid that is capable of super oxygenation, including flavored water and other ingestive beverages, and saline solutions.
Objects of the present invention include enabling the production of a liquid enriched with dissolved oxygen at higher oxygen concentrations, particularly at atmospheric pressure, than has been possible through apparatuses and processes according to the prior art, and to do so at industrial scale, continuous production rates.
Another object of the present invention is to provide improved aerobic, therapeutic and fermentation processes, and saline solutions, employing liquids highly enriched with oxygen in accordance with the present invention.
The present invention provides an apparatus for oxygenating a liquid, including a liquid pump, supply piping having an inlet connected to the pump and an outlet, first and second injectors and a chamber. The first injector has a liquid inlet forming a nozzle, a liquid outlet and an oxygen inlet, the first injector oxygen inlet intermediate the first injector liquid inlet and outlet, the supply piping outlet connected to the first injector liquid inlet. The second injector has a liquid inlet forming a nozzle, a liquid outlet and an oxygen inlet, the second injector oxygen inlet intermediate the second injector liquid inlet and outlet, the first injector liquid outlet in communication with the second injector liquid inlet, whereby liquid flows through the first and second injectors in series, each of the first and second injector oxygen inlets provided with a source of oxygen gas. The chamber has a liquid inlet and a liquid outlet, the second injector liquid outlet in communication with the chamber liquid inlet, whereby liquid flows through the second injector and the chamber in series.
The present invention also provides a process for enriching a liquid with oxygen, which includes the steps of: (a) introducing a liquid under pressure into a first injector and flowing the liquid downwardly through the first injector; (b) introducing oxygen into the liquid as it flows through the first injector to mix the liquid and oxygen; (c) introducing the admixture of liquid and oxygen resulting from the step (b) under pressure into a second injector and flowing the liquid downwardly through the second injector; (d) introducing oxygen into the admixture as it flows through the second injector to further mix the liquid and oxygen; (e) introducing the admixture of liquid and oxygen resulting from step (d) into a chamber, wherein undissolved oxygen is released from the admixture introduced into the chamber and is collected in the chamber; and (f) recovering an oxygen enriched liquid from the chamber.
The present invention also provides a physiological saline solution which includes as the solvent an oxygen enriched liquid, the liquid having an oxygen concentration level of at least about 160 mg/l. The present invention also provides a process of preparing a physiological saline solution which includes the steps of: providing an oxygen enriched liquid having an oxygen concentration level of at least about 160 mg/l; and dissolving a sodium concentrate into the oxygen enriched liquid.
The present invention involves processes for using oxygen enriched liquid prepared in accordance with the preparatory process of the present invention and by the use of the apparatus of the invention. These processes of use include aerobic, disinfection, therapeutic and fermentation processes advantageously employing oxygen-containing liquids, as described above.
If desired, liquids treated in accordance with the present invention can also be made effervescent by the addition of a gas such as carbon dioxide. If carbon dioxide is added after the dissolution of the oxygen in the water, then it will displace a portion of the dissolved oxygen. It has been found, however, that an effervescent liquid can be further enriched with oxygen to a substantial degree after the addition of the carbon dioxide. Even more oxygen can be dissolved in the liquid if the liquid being enriched with the oxygen is chilled at the time of the oxygen enrichment. To an even greater extent than achievable by chilling the liquid, the solubility of oxygen in a liquid may be increased by increasing the pressure of the liquid and oxygen admixture.